I actually think I could do 12. Before a game I usually pregame a bit (1-4 only) then stick to 2 per period.
The only reason I don't think I could do 12 is because it would make an event out of just drinking. Normally I do 2 a period just because I only go during intermission, and sometimes don't even get back to my seat in time for the puck drop. If my friends had my back, and were getting beers for me so I could concentrate on drinking/peeing alone. I think it's easily possible.
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